The liquid crystal display possesses advantages of thin body, power saving, low radiation and soft image of not hurting eyes, and is the main stream display in the present display market. According to the different alignment directions of the liquid crystal molecules, the liquid crystal displays can be categorized as IPS display, VA display and FFS display (Fringe Field Switching). Compared with other displays, the FFS display has better wide view angle effect, which is the wide view angle technology developed by the liquid crystal industry for solving large scale, high resolution desktop display and liquid crystal TV applications.
The FFS liquid crystal display technology is mainly to generate a fringe electrical field with electrodes inside a pixel in a plane. Utilizing the fringe electrical field, the oriented liquid crystal molecules between the electrodes and right above the electrodes can be rotated, converted along the direction parallel with the substrate plane. Thus, the transmittance of the liquid crystal layer can be promoted. Under the premise of wide view angle, the high transmitting efficiency can be realized in advance. As shown in FIG. 1, the pixel structure of the FFS liquid crystal display according to prior art comprises a pixel electrode 11, a gate line 12 applying scan signals, a data line 13 applying data signals and a transistor switch 14. As shown in FIG. 1, the pixel electrode comprises a terminal electrode branch 11a and a plurality of sub electrodes 11b. The terminal electrode branch 11a is connected to the plurality of sub electrodes 11b. Crack structures exist among the plurality of sub electrodes 11b, which are employed as the flow openings of electrical field. Besides the sub electrode 11b comprises top and bottom two parts connecting with each other. The top and bottom two parts have V shape structures. Thus, as the voltage is applied to the pixel electrode, as shown in FIG. 2, the liquid crystal molecules 15 can be aligned along two different directions, and accordingly, the better wide view angle effect can be obtained.
When the liquid crystal display is compressed by a larger external stress, the alignment directions of the liquid crystal molecules 15 can be changed easily. Particularly, the liquid crystal molecules at the juncture of the top and bottom two parts of the sub electrode 11b where the electrical field is weaker can be influenced by the external force more easily. As shown in FIG. 3, as being compressed by the external stress, the alignment direction of the liquid crystal molecules 15′ corresponding to the top electrode part is changed from the upward twist in normal condition to the downward twist. However, because the top and bottom two parts of the sub electrode 11b connect with each other, the fringe electrical field generated at the juncture of the two parts of electrode is weaker, which causes that the liquid crystal molecules are hard to be controlled to be rapidly recovered to the normal twisted directions as the external force disappears. It results in the poor recovery of the liquid crystal molecules and the image quality is influenced.